From c5f888cae49dfe3e86d9d1e0dab2b63ceb057be3 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 12 May 2008 21:20:55 +0200 Subject: [PATCH] ftrace: irqsoff use raw_smp_processor_id This patch changes the use of __get_cpu_var to explicitly calling raw_smp_processor_id and using the per_cpu() macro. On some debug configurations, the use of __get_cpu_var may cause ftrace to trigger and this can cause problems with the irqsoff tracing. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- kernel/trace/trace_irqsoff.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index d0c1748b1e..761f3ec66c 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -204,14 +204,14 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip) if (likely(!tracer_enabled)) return; - if (__get_cpu_var(tracing_cpu)) + cpu = raw_smp_processor_id(); + + if (per_cpu(tracing_cpu, cpu)) return; - cpu = raw_smp_processor_id(); data = tr->data[cpu]; - if (unlikely(!data) || unlikely(!head_page(data)) || - atomic_read(&data->disabled)) + if (unlikely(!data) || atomic_read(&data->disabled)) return; atomic_inc(&data->disabled); @@ -225,7 +225,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip) trace_function(tr, data, ip, parent_ip, flags); - __get_cpu_var(tracing_cpu) = 1; + per_cpu(tracing_cpu, cpu) = 1; atomic_dec(&data->disabled); } @@ -238,16 +238,16 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip) struct trace_array_cpu *data; unsigned long flags; + cpu = raw_smp_processor_id(); /* Always clear the tracing cpu on stopping the trace */ - if (unlikely(__get_cpu_var(tracing_cpu))) - __get_cpu_var(tracing_cpu) = 0; + if (unlikely(per_cpu(tracing_cpu, cpu))) + per_cpu(tracing_cpu, cpu) = 0; else return; if (!tracer_enabled) return; - cpu = raw_smp_processor_id(); data = tr->data[cpu]; if (unlikely(!data) || unlikely(!head_page(data)) || @@ -255,6 +255,7 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip) return; atomic_inc(&data->disabled); + local_save_flags(flags); trace_function(tr, data, ip, parent_ip, flags); check_critical_timing(tr, data, parent_ip ? : ip, cpu); @@ -376,7 +377,7 @@ static void stop_irqsoff_tracer(struct trace_array *tr) static void __irqsoff_tracer_init(struct trace_array *tr) { irqsoff_trace = tr; - /* make sure that the tracer is visibel */ + /* make sure that the tracer is visible */ smp_wmb(); if (tr->ctrl) -- 2.39.5